Posts Tagged ‘food chemistry’

In my younger days in high school, I had to literally suffer through chemistry. I had a teacher who resembled a walrus: Bald head and huge mustache. He spoke in a monotone and no, his incisors were not protruding down his face, but thinking about it now, I could draw those in and chuckle!

Walrus – Photo by DK Images

He was as dry in his lectures as an August day in the Mojave Desert. Do I remember anything I learned in his class? No. I passed with a C.

Why am I telling you this? Because if this class had been taught around the chemistry with food, it would have held my interest. All these years later, I have come to realize that there is chemistry in cooking. And, I have discovered that this is now a subject taught in colleges. Maybe it was a student of Food Chemistry that came up with the meat glue!  Anyway, the topic is worthy of a blog. Chemistry is involved in our lives in a number of ways, but the focus here is food. So here are some interesting facts that involve chemistry and food.

Cooking is all about chemical reactions. Chemistry is all about how things react. Therefore cooking is chemistry! Now let’s take a look at some of these reactions.

**If you put chopped red cabbage into a hot pan, the heat breaks down the red anthocyanin pigment in the vegetable, which causes the cabbage to change color to a blue. This reaction causes the the acids in the vegetable to turn to alkaline. To regain the color, if you add vinegar, you increase the acidity, and the color will go back to the red.

**Cooking green vegetables by dropping them into boiling water causes a unique reaction. When the tiny air cells in the vegetable hits the boiling water, they become a brighter green. Quick cooking of green vegetables keeps the green color, and the longer you cook the green vegetable, the cells break down and shrink, causing a release of acid turning your vegetable the color of canned green beans.

Canned green beans – Photo from Food.com

**All the years of fishing on the ocean has taught me one thing regarding food on a boat: Bananas are not allowed! Why? Because the bananas give off ethylene gas which causes food to spoil.  Bananas on a boat with limited space in the galley in the olden days caused a lot of spoilage of foods! Why they do not mind apples is beyond me, because apples do the same thing.  If you need an avocado ripened, put it in a brown paper bag with a banana or an apple and it will be ready to use the following day.

**Have you ever cooked a lasagne, had leftover’s and then covered it with aluminum foil to store overnight in your refrigerator? The next day, have you noticed that the surface of the foil has been eaten away where the foil touched the tomato sauce? This is a chemical reaction from the acids in the tomatoes with aluminum. Acidic vegetables and fruits react negatively with aluminum. And the aluminum can poison you. Acidic foods such as tomatoes and citrus, and do not forget pineapple, should be prepared in glass.

**Thawing frozen foods, melting butter, dissolving sugar, salting meat or fish involve chemistry. The components of each of these processes creates a chemical change in the structure of these foods.

Melting butter

**Heat, no matter what method you use, increases the speed of the molecules in the food. The greater the speed, the more the molecules collides. This leads to changes in the molecular structure of the foods, which creates different characteristics, colors, flavors and textures.   Don’t you just love chemistry?

**The Maillard Reaction: This occurs during grilling. An amino acid in the food and a reduction of sugars in the food creates new compounds, resulting in foods that are very tasty.

**Caramelization results from breaking down proteins into simple sugars creating a sweeter flavor.

**If you do not incorporate the dry ingredients equally for a cake, or a bread, you will end up with a cake or a bread that doesn’t rise properly.

**While cooking, you might prefer a wooden spoon to a metal spoon. Why? Because the metal spoon will transmit more heat, known as thermochemistry, than a wooden spoon.

**”A watched pot never boils.” You have heard that statement haven’t you? Leaving the lid off of a pot of water that you want to boil takes longer to boil, ergo the statement, as heat is lost with the lid off…You knew this already, didn’t you? Putting the lid on the pot actually lowers the boiling point. This is known as the Third Law of Gas.

A watched pot – Photo from BarefootKitchenWitch com

**Boiling causes foods to become more tender.

**Adding salt to water that you need to boil  lowers the boiling point.

**If you add too much butter or oil to a dish, you will see it pooling around the surface of what you are making. You have overrun the saturation point of what it is you are trying to create. Just another example of how chemistry works in the kitchen!

**50% of meat products and 95% of vegetable products are water. This makes an excellent growing stage for bacteria. So, a key in preservation of food is to reduce the amount of water in a food. Dehydration removes the water and creates foods that can be reconstituted later.

**Other items of chemistry in food: Carbohydrates; Lipids; Proteins; Enzymes; Vitamins; Minerals…and the list goes on.

So, if you have a child, who is suffering with chemistry, maybe you might want to take some time and take them on a trip around the kitchen!

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